000
FXUS63 KDVN 310847 CCA
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
346 AM CDT FRI JUL 31 2015
.SYNOPSIS...
ISSUED AT 346 AM CDT FRI JUL 31 2015
HIGH PRESSURE WAS LOCATED ACROSS MO THIS AM AS LIGHT WESTERLY
WINDS WERE REPORTED ACROSS THE AREA. NW H5 FLOW CONTINUED ACROSS
THE AREA AND AS LEADING TO SLIGHTLY DRIER AIR ACROSS THE AREA. A
H85 JET WAS MOVING INTO THE AREA FROM THE NW. A WEAK SFC TROF WAS
LOCATED FROM DULUTH TO JUST NORTH OF ABERDEEN SD. THIS SFC TROF
AND H85 JET WILL BE THE DOMINATE WEATHER PLAYERS IN THE SHORT TERM
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT FRI JUL 31 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR POPS
ACROSS FAR SOUTHERN ZONES TODAY INTO THIS EVENING. WEAK FORCING
LOOKS TO LIMIT OVERALL COVERAGE OF PRECIPITATION AND LEADS TO LOW
CONFIDENCE IN PRECIP OCCURRING.
SFC TROF...WEAK H85 CONVERGENCE AND DAY TIME HEATING LOOKS TO BE
THE MAIN FORCINGS FOR PRECIP LATER TODAY. LARGE SCALE MODELS POP
QPF ACROSS SW AND S PORTIONS OF IA FROM 18Z THROUGH 06Z TODAY. AS THE
SOUTHWARD MOVING SFC TROF MOVES THROUGH THE AREA...OUR CHANCES FOR
POPS WILL LEAVE WITH IT. HIRES CAMS ALSO POP QPF ACROSS THE AREA
FROM 21Z TO 03Z. WITHOUT STRONG FORCING...WILL KEEP POPS IN THE
SCHC REALM.
H85 JET ADVECTING INTO THE AREA WILL LEAD TO WINDS NEAR 20 KNOTS
AND GUSTS TO 30 KNOTS ACROSS OUR NE. THESE WINDS WILL LIKELY
RESULT IN DRIER AIR BEING MIXED TO THE SFC AND THUS A DIFFICULT
DEWPOINT FORECAST FOR THE DAY TODAY. REGARDLESS...WITH HIGHS IN
THE 80S AND DEWPOINT TEMPS IN THE 50S WITH MODERATE WINDS....IT
SHOULD BE AN OVERALL BEAUTIFUL SENSIBLE WEATHER DAY.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 346 AM CDT FRI JUL 31 2015
ACTIVE/UNSETTLED NORTHWEST FLOW TO RESULT IN PERIODIC PRECIPITATION
CHANCES... AND EVENTUAL COOLER TEMPS NEXT WEEK.
SATURDAY AND SATURDAY NIGHT...ANTICIPATE AT LEAST SOME RAIN CHANCES
DEVELOPING ESPECIALLY BY SATURDAY EVENING INTO THE OVERNIGHT
ATTENDANT TO MOIST TRANSPORT AND CONVERGENCE WITH VEERING LOW LEVEL
JET. CONFIDENCE IS LOW ON EXTENT OF STORM COVERAGE AS NAM/GFS
DEEPER BY 2-4+ MB WITH NORTHERN PLAINS SURFACE LOW AND SHARPER ON
DEFINITION OF WARM FRONTAL STRUCTURE AND STRONGER WITH LOW LEVEL
WIND FIELDS AND ATTENDANT CONVERGENCE... WHILE ECM WEAKER AND MORE
DIFFUSE. SPC HAS NEARLY THE ENTIRE CWA IN SLIGHT RISK OF SEVERE
STORMS...AND CANNOT DISCOUNT AT LEAST ISOLD SEVERE STORM POTENTIAL
ESPECIALLY WEST OF THE MISSISSIPPI RIVER WHERE MODELS GENERALLY
DEPICT ENVIRONMENT WITH MUCAPE AROUND 1000-1500 J/KG AND 25-30+ KTS
OF SHEAR 0-6KM AGL. EXPECT MORE HUMID CONDITIONS TO GO ALONG WITH
VERY WARM/HOT TEMPS WELL INTO THE 80S MOST AREAS WITH SOME LOCATIONS
POSSIBLY 90 OR LOWER 90S ESPECIALLY SOUTHWEST 1/2 OF CWA DEPENDING
ON AMOUNT OF SUNSHINE.
SUNDAY AND SUNDAY NIGHT...MAINTAINED CHANCE POPS FOR SLOW DECAYING OF
LINGERING PRECIP PROCESSES SUNDAY AM AND POTENTIAL REDEVELOPMENT ON
ANY RESIDUAL OUTFLOW BOUNDARIES BY MID TO LATE AFTERNOON INTO
EVENING. HOWEVER...LOWER CONFIDENCE WITH PRECIP CHANCES HERE AS SOME
POTENTIAL FOR EML TO ADVECT INTO AREA AND CAP THINGS
OFF...ESPECIALLY IF MORE ROBUST CONVECTION /MCS/ OCCURS EARLY SUNDAY
AM. HIGH TEMPS WILL BE CHALLENGING DUE TO POTENTIAL CONVECTIVE
DEBRIS... BUT BANKING ON AT LEAST PARTIAL SUNSHINE TO BOOST TEMPS
INTO THE 80S DURING THE AFTERNOON TO GO ALONG WITH HUMID CONDITIONS.
MONDAY THROUGH THURSDAY...THROUGH MIDWEEK IT APPEARS CWA WILL RESIDE
NEAR THE BATTLE GROUND BETWEEN HEAT DOME OVER ROCKIES INTO PLAINS
AND UPPER LOW AND COOLER TEMPS AROUND THE GREAT LAKES. THIS WILL
RESULT IN SURFACE FRONT NEAR THE REGION WITH PERIODIC RAIN CHANCES
AS UPPER LEVEL DISTURBANCES PROPAGATE DOWN ACROSS THE REGION IN
NORTHWEST FLOW. DUE TO TIMING CHALLENGES AIDED BY MODEL SMOOTHING OF
LOW AMPLITUDE WAVES UNFORTUNATELY HAVE TO CARRY DAILY RAIN CHANCES.
THE WEEK LOOKS TO START OFF SEASONAL ON TEMPS BUT WITH TIME DO
ANTICIPATE A DOWNWARD TREND TO BELOW NORMAL WITH INFLUX OF COOLER
AIR IN WAKE OF PASSING GREAT LAKES SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1133 PM CDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL THROUGH THIS TAF PERIOD. A HIGH
PRESSURE SYSTEM IS FORECAST TO SLIDE TO THE SOUTHWEST OF THE UPPER
MIDWEST TONIGHT AND FRIDAY. A WAVE OF MID-LEVEL INSTABILITY MAY
PRODUCE AN ISOLATED SHOWER OR STORM THROUGH FRIDAY MORNING BUT
DID NOT MENTION IN TAFS DUE TO EXPECTED ISOLATED NATURE/LOW
COVERAGE. DAYTIME MIXING INTO STEADY WINDS ALOFT WILL CREATE
BREEZY CONDITIONS FRIDAY AFTN WITH WNW GUSTS BETWEEN 20-25 KTS.
UTTECH
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...05
AVIATION...UTTECH